In Vedic religion, we have 3 bodies namely Gross , Astral and Causal bodies - also known as STHUL SUKSHMA AND KARAN SHARIR. In that concept we also have concept of Physical Brain and also Astral Brain. The concept of NADI is also well known and There are 72000 Nadis and some feel that we have more than 72000 Nadis .So in Astral spine there are 3 Nadis which are main The SUSHUMNA is the central one and on it's each side is IDA , which is one left side and PINGALA , which is on right side of the Sushumna nadi. I think that may be the replication of physical spine and which is SUSHUMNA and the sympathetic chain and parasympathetic nervous system may be the IDA and PINGALA. Some feel that IDA and PINGALA are duality like SHIV and SHAKT or Feminine and Masculine or Intellect and Intuition .
The SUSHUMNA extends from MULADHAR CHAKRA which is at coccygeal area to Brain. It provides power of expansion, contraction all the activities of motion of Astral spine. Within the SUSHUMNA is the spine called VAJRA and that extends from SWADHISTAN CHAKRA which is at sacral spine area Within the VAJRA is the CHITRA SPINE . which controls the spiritual activities . The VAJRA spine is helpful for motion of the astral body and provides power of expansion and contraction of the astral spine.
The BRAHMANADI is described as inside CHITRA spine . It could be considered as spine from CAUSAL BODY or KARAN SHARIR. It is thoughts, vibration or consciousness. When we say 'inside ' it is not physically inside , but for out concept we use the terms like 'inside' and 'outside'.
The Astral Brain has the Consciousness or Reflected Consciousness. It descends through the spine and gives the qualities of each Center or CHAKRA .It manifests as Wisdom in Causal Brain, Intuition in Medulla, Calmness in cervical center ,Self control in lumbar area and Restraint in Coccygeal center.
The BRAHMARANDRAH is the opening on the top of skull through with the energy enters the spine. It is present in new born infant and then it closes in physical body. The same thing can be said in Astral Brain and spine.
